Barium sulfate (BaSO) was considered to be poorly-soluble and of low toxicity, but BaSO NM-220 showed a surprisingly short retention after intratracheal instillation in rat lungs, and incorporation of Ba within the bones. Here we show that static abiotic dissolution cannot rationalize this result, whereas two dynamic abiotic dissolution systems (one flow-through and one flow-by) indicated 50% dissolution after 5 to 6 days at non-saturating conditions regardless of flow orientation, which is close to the in vivo half-time of 9.6 days. Non-equilibrium conditions were thus essential to simulate in vivo biodissolution. Instead of shrinking from 32 nm to 23 nm (to match the mass loss to ions), TEM scans of particles retrieved from flow-cells showed an increase to 40 nm. Such transformation suggested either material transport through interfacial contact or Ostwald ripening at super-saturating conditions and was also observed in vivo inside macrophages by high-resolution TEM following 12 months inhalation exposure. The abiotic flow cells thus adequately predicted the overall pulmonary biopersistence of the particles that was mediated by non-equilibrium dissolution and recrystallization. The present methodology for dissolution and transformation fills a high priority gap in nanomaterial hazard assessment and is proposed for the implementation of grouping and read-across by dissolution rates.
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http://dx.doi.org/10.1038/s41598-019-56872-3 | DOI Listing |
Gels
January 2025
Institute of Nanotechnology and Advanced Materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
Researchers have been investigating the physical and morphological properties of biodegradable polymer and copolymer films, blending them with other chemicals to solve challenges in medical, industrial, and eco-environmental fields. The present study introduces a novel, straightforward method for preparing biodegradable hydrogels based on polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) for medical applications. The resulting PVA/PVP-based hydrogel uniquely combines the water absorbency, biocompatibility, and biodegradability of the polymer composite.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Food and Bioengineering, Zhengzhou University of Light Industry, Zhengzhou 450001, PR China; Key Laboratory of Cold Chain Food Processing and Safety Control (Zhengzhou University of Light Industry), Ministry of Education, Zhengzhou 450001, PR China. Electronic address:
Oral fast dissolving films represent a novel dosage form for probiotics. To reduce the dependence of film preparation on synthetic materials, a polysaccharide-based oral fast dissolving nanofilm for probiotics was fabricated through pullulan (PUL) electrospinning. An electrospinnability map of PUL with varying physical properties was developed, identifying a molecular weight of 200 kDa and a concentration of 20 % as suitable conditions for achieving favorable fiber morphology.
View Article and Find Full Text PDFChemosphere
January 2025
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstraße 1-3, 24148, Kiel, Germany; Christian-Albrechts University Kiel, Institute of Geosciences, Ludewig-Meyn-Str, 24118, Kiel, Germany.
Relic munitions from warfare and intentional dumping contaminate coastal waters worldwide, with an estimated 300,000 tons in the German Baltic Sea alone. These contain toxic conventional explosive chemicals, including 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX), and 1,3-dinitrobenzene (DNB). Corrosion of metal munition housings in seawater releases these munition chemicals (MCs) to the marine environment.
View Article and Find Full Text PDFACS Biomater Sci Eng
January 2025
CEA, DES, ISEC, DPME, SEME, University of Montpellier, Marcoule, Bagnols-sur-Cèze F-30207, France.
Although models have been proposed to explain the mechanisms of bioglass (BG) dissolution and subsequent calcium phosphate (CaP) mineralization, open questions remain. The processes in which phase transition occurs in aqueous solutions and their dynamics remain underexplored partly because traditional instruments/techniques do not allow for direct observations at the adequate time and length scales at which such phase transformations occur. For instance, given the crucial role of the silica gel in CaP formation during BG dissolution, uncertainty exists about how such a silica gel forms on the BG surface.
View Article and Find Full Text PDFWater Res
January 2025
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China; College of Environment and Resources, Xiangtan University, Xiangtan, Hunan 411105, PR China. Electronic address:
A sustainable supply of lithium from salt-lake brines is necessary due to the surge in demand of the lithium-battery market. However, the presence of coexisting ions, particularly Na, poses a significant challenge due to the similarities in charge, electronic structure, and hydrated size. The electrochemical system with manganese (Mn)-based lithium-ion (Li) sieves electrodes is a promising method for Li recovery, but often suffers from geometric configuration distortion, which reduces their selectivity and capacity.
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